The long-running environmental lawsuit against Chevron Corp. in Ecuador has pitted whole armies of lawyers, activists and technical experts against each other.

Now a former combatant appears to have switched sides.

An author and petroleum engineer who used to work for the lawyers suing Chevron has given the company a sworn statement in which he accuses his former colleagues of trying to dictate, in advance, the outcome of supposedly independent court reports on oil-field contamination in Ecuador.

The lawyers wanted ammunition that would force Chevron to clean up a portion of the Amazon rain forest where Texaco, bought by Chevron in 2001, used to drill for oil. But in his statement, engineer Fernando Reyes says three of the lawyers "acknowledged that the judicial inspection process had not yielded data to support their claims of contamination."

Chevron has made the same accusations for years, arguing that the closely watched case has been hopelessly tainted by fraud.

An Ecuadoran judge ruled against Chevron last year, ordering the San Ramon company to pay $19 billion. Chevron has vowed not to hand over the money and has sued the other side's lawyers for extortion and racketeering. The Ecuadoran team is now pursuing Chevron's assets in Argentina, Brazil and Canada to collect on the judgment.

Racketeering suit

Chevron obtained Reyes' statement as part of the racketeering suit. Company spokesman Kent Robertson said Reyes was not paid for his statement, nor was he promised work with Chevron.

"The fraud is going to come out, and he wants to be on the right side," Robertson said.

Karen Hinton, a spokeswoman for the Ecuadorans' legal team, accused Chevron of ghostwriting some of Reyes' comments, and said her team had not tried to force Reyes or anyone else to compromise their professional ethics. She also insisted that tests showed extensive oil-field contamination in the area.

"Reyes either lies or is mistaken when he claims that the plaintiffs acknowledged that the data from the judicial inspections did not support their claims," she said.

Reyes became involved in the suit at the end of 2005. He had just published a book "Oil, Amazon, and Natural Capital," arguing that Chevron and the Ecuadoran government together needed to clean up the oil fields.

Steven Donziger, an American attorney who was leading the Ecuadoran legal team, asked Reyes and the head of an Ecuadoran engineering association to review the work of court-appointed experts who were analyzing contamination tests.

Reyes agreed to work as a "monitor" along with the engineering association head, Gustavo Pinto. Although the plaintiffs would pay him, Donziger didn't want Reyes to reveal that to the court, according to the statement.

"Mr. Donziger told us his goal was to create the image that the monitorship was 'independent' of the parties, so that it would be received with deference and respect by the court," Reyes said.

Attacking the work

When the court-appointed experts turned in a report that Donziger didn't like, Donziger asked Reyes and Pinto to submit a paper on the engineering association's letterhead attacking the experts' work, according to Reyes.

"During our discussions, Mr. Dozinger (sic) told us that our report should establish that the findings of the settling experts' report ... were wrong, that they lacked objectivity and were biased toward Chevron, and therefore the report should be discounted," Reyes said. "However, in my professional opinion the evidence did not support Mr. Donziger's position and I could not twist my professional assessments to make them fit the plaintiffs' interests."

According to the statement, Donziger later tried to persuade the judge in the case to appoint Reyes as an independent expert who would conduct a "global assessment" of damages for the court.

"Mr. Donziger told me in the meeting what would be expected of me in the role of expert," Reyes said. "Mr. Donziger emphasized the need for the expert to state that Chevron was the only party responsible for the environmental damages and the harm to the local community."

Reyes said, however, that he felt uncomfortable with the idea of serving as the court's independent expert and he suggested another consultant, Richard Cabrera. In 2007, Reyes, Cabrera, Donziger and several other of the plaintiffs' lawyers met to discuss the global assessment.

At the meeting, Donziger and the other lawyers "dropped any pretense that Mr. Cabrera would act independently in writing an expert report that would be technically sound and executed according to professional standards," Reyes said in the statement. "On the contrary, it was obvious that the plaintiffs had already predetermined the findings of the global assessment, that they themselves would write a report that would support their claim for billions of dollars against Chevron and would simply put Mr. Cabrera's name on it."

Chevron has claimed for years that the lawyers ghostwrote Cabrera's report, while the lawyers insist they merely submitted information to him that he was free to use. Chevron could have done the same, they say.

"Given that Chevron boycotted the Cabrera process, the company is in no position to complain that he relied on materials presented to him by the plaintiffs, consistent with court orders in Ecuador," Hinton said. The judge who ruled against Chevron eventually decided not to use Cabrera's report due to the controversy.